A retail businesses (example: Relaince, payback cards) will store the customer details in a table and table has columns CustomerID, Customername, city,state,mobille number. Here, customer id is unique and can't be same to more than one person.

Whenever, i do shopping , i will give my mobile number or CustomerID and they will updated the points to my CustomerID .Here, CustomerID exists in real world ,

Can i say CustomerID is natural key ?

order ID and product ID: In product table product ID and order table has order ID are unique, order ID and product ID are not natural key, Right ?

Like same, bank account number will be unique.Bank account number also natural key and business key ?